


I Liked It

by BasuraSinBin



Category: Undertale (Video Game)
Genre: Anal Fingering, Anal Plug, Anal Sex, Attempt angst?, Blow Jobs, Butt Plugs, Cock Rings, Collars, Deepthroating, Dubiously Consensual Blow Jobs, Ecto-Genitalia (Undertale), Ecto-Penis (Undertale), Ecto-Tentacles (Undertale), Ecto-Tongue (Undertale), Fluff and Smut, Forced, Forced Orgasm, Incest, Kissing, Leashes, Light Bondage, M/M, Mild Cum Inflation, Mild Hurt/Comfort, Multiple Orgasms, NSFW, Neck Kissing, Orgasm Delay/Denial, Overstimulation, Rape/Non-con Elements, Rough Kissing, Sibling Incest, Siblings, Smut, Tentacle Sex, Tentacles, Twincest, Twins, Vibrators
Language: English
Status: Completed
Published: 2019-11-01
Updated: 2019-11-01
Packaged: 2021-01-05 11:07:46
Rating: Explicit
Warnings: Rape/Non-Con
Chapters: 1
Words: 3,576
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/21207533
Author URL: https://archiveofourown.org/users/BasuraSinBin/pseuds/BasuraSinBin
Summary: Dream really wants his brother, in more ways than one.





	I Liked It

Nightmare fidgeted under Dream’s stare, tentacles squirming in anticipation. He glanced sideways at the smaller skeleton.

Dream laid on his stomach, hands on each cheek and propping up his head. His usual star like pupils were now hearts as he gazed lovingly at the gooey skeleton.

Nightmare snapped his eyes forward, keeping them trained on the movie they were supposed to be watching.

He drummed his fingers on the mattress as he was unable to distract himself from the smol brother.

Nightmare’s tentacles wavered around him, uselessly protecting himself from Dream’s sight.

Nightmare wrapped some covers around his shoulders as he hugged his legs close to his chest. He dug himself deeper into the cocoon of blankets in further attempts to hide.

He jumped as he heard Dream giggle but his statement made him blush.

“Nightmare, you’re so cute <3”

Cerulean coated his cheeks as he peeked out of the blankets.

The undeniable yellow glow of Dream’s blush dusted across his cheeks as he watched Nightmare in a more dreamy state.

Nightmare stammered in his words, unknowing what he could say in the situation. He just quickly looked away and covered himself more with his tentacles.

“Aww~ Nighty, there’s no need to be shy around me,” Dream beckoned as he crawled closer to the bundle of blankets. Nightmare only buried himself further.

Dream clicked off the TV. The silence made a sliver of dread tear through Nightmare but he refused to show any sign it.

Dream attempted to wrap his arms around Nightmare, but he was unable to due to the wrapping tentacles and blanket cocoon. He huffed and pouted.

“Nightmaaaaare,” he whined. “Stop hiding from meee! Get outta there, will you?”

Dream, hearing Nightmare’s muffled denial, sighed in annoyance. He made his way behind Nightmare and pulled the blankets off his shoulders.

Nightmare shivered as his protection and warmth left him. His tentacles reacted, moving around in further attempts to cover the monster.

Tentacles weren’t going to stop Dream, though. Dream slipped his arms over Nightmare’s shoulders and around his neck. Nightmare shivered as Dream teasingly breathed on the nape of his neck.

Dream managed to find a way to Nightmare’s lap. He plopped himself down and stared into the cerulean of his brother’s eye. The blue of Nightmare’s blush glowed brightly as Dream moves his face closer to the other’s.

Dream wrapped his arms around Nightmare’s tense body as he leaned closer. Nightmare shivered as Dream breathed on his neck. “I love you, brother.”

A sudden surge of energy flowed throughout Nightmare’s body. His once tense body unwinded, the protective tentacles falling by his side on the surrounding blankets. He slouched, feeling a little drowsy.

Nightmare groaned weakly. “Dream... wha...what did you do...?” He drew out a distraught whimper as Dream giggled.

“There’s no need to worry, brother! You just have to stay positive...” Dream soothingly stroked Nightmare’s skull, making him feel strangely calm.

It struck Nightmare that his brother had used his positive energy in attempts to weaken him. He sluggishly looked up at Dream, fighting to keep his eye open.

A large grin etched across Dreams face. He continued to caress his head with soft touches. Dream pulled the vulnerable Nightmare onto his lap. “Nightmare, you should go into your passive form. It’ll help you~” Dream purred into Nightmare’s ear.

Nightmare gave the other a tedious glare. Not only had he hated his passive form but what Dream said was a complete and utter lie. But he knew he couldn’t stop it. He was too weak to verbally refuse and his half-lidded eye could only process so much as he drifted into a half-consciousness state.

Nightmare rested his skull on Dream’s shoulder. He felt heavy.

The dark goo and slime seemed to melt away, slipping and sliding off the now white bones. His now current lavender eyes couldn’t remain open. Nightmare felt darkness take over as his sockets finally closed.

Dream giggled brightly as he shifted around. Alarmed, Nightmare fought to stay awake. He might not be able to see or move but he refused to slip into unconsciousness.

Dream’s lips brushed against Nightmare’s ear once again. “Seeing you like this makes me horny,” Dream asserted in a hushed whisper.

That statement made Nightmare snap his eyes open and jerk back, though he was still caught in Dream’s embrace. “What?” Nightmare inquired in a choked whisper, more like a gasp.

Nightmare suddenly fell limp once again as he drowned in Dream’s positivity. He glared at Dream, eyes once again struggling to stay open.

Dream smiled at him dearly before bringing him closer into a deep kiss. Nightmare feebly attempted to push Dream away. Dream slipped his tongue into Nightmare’s mouth, the latter’s sockets squeezed shut and his hands gripped as tightly they could onto Dream’s arms. Dream smiled as he closed his sockets as well and pushed the back of Nightmare’s skull to deepen the kiss.

They parted with a trail of saliva, both gasping. Nightmare’s eyes flitted away as a pale lavender flushed his cheeks. Dream smiled warmly before lightly brushing the other’s cheek and pulling him into a quick hug. Nightmare laid his head on Dream’s chest, hesitantly hugging back as his thoughts drifted to what just happened.

He just buried his face into Dream’s cape, unwilling to look at the other. He seemed to tone down on the positivity output but he could easily pump more out. Nightmare was completely at Dream’s mercy.

He felt Dream shuffle around and heard some clattering. He peeked out to see him looking around in a cardboard box. Raising a skeptical eyebrow, he leaned closer to see what the younger was doing.

His stomach dropped as Dream made eye contact. He had a delirious look in his eye as he pulled out a collar and leash. Nightmare immediately fell limp again as Dream fastened the object to Nightmare. He grinned approvingly at his work as Nightmare breathed a shaky sigh.

Dream harshly tugged on the leash, satisfied as the monster on his lap sat upright. His heart fluttered as he witnessed Nightmare adorably paw at the collar, cheeks puffed out for a pout.

Nightmare paused as the other pulled down on the collar to expose bare bone. Dream dragged his tongue across the surface of Nightmare’s neck, digging the tip into the crevices every so often.

Nightmare whimpered, body shaking heavily. “D-Dream…s-stop—” He attempted to pull himself from the other’s hold, but Dream just tugged on his restraint, forcing him back.

Nightmare closed his eyes tightly, tears threatening to spill, as Dream found a sensitive area on his neck. A strangled cry escaped him as Dream sunk his teeth into bone, drawing blood. Nightmare shut his mouth quickly, unwilling to let Dream hear more. He whined as bright, violet tears spilled down his cheeks.

Dream lapped up the crimson blood and kindly wiped away his brother’s tears. Nightmare sniffled as both siblings connected gazes. Dream stared, deeply entranced by Nightmare’s glowing orbs. They were filled with an unusual innocence and fear.

Nightmare averted his gaze and wiped his own tears. “Please…Stop… please!...”

Dream watched as Nightmare cast his gaze on the hands resting on his own lap. Tears fell, dampening Nightmare’s clothes and rolling down bone. He brought his hands to his face, trying to halt the flow of tears.

Guilt ebbed away at Dream’s insides as he witnessed the other sniffle and cry, even hiccup on certain occasions. Dream held back his own tears from seeing his brother so broken from his actions and pulled him into a tight embrace.

Nightmare wrapped his arms around the other, shaking violently, as he sobbed. Dream whispered quiet apologies and tears broke out. He held his brother like he was his child, pulling Nightmare closer as both wept.

After a few moments of regret and sorrow in the room, both were able to calm down. Dream loosened his hold as he stared at Nightmare’s face.

Nightmare gazed back, sniffling once more. Dream looked down, muttering “I’m sorry,” for the millionth time.

Nightmare cupped Dream’s cheeks, taking him by surprise. Dream glances up, taken aback as Nightmare seemed to be crying once again. Thoughts raced through his mind as he panicked, only freezing when Nightmare rested his head on Dream’s shoulder.

“Dream, I can feel your guilt… please. I’m fine. Don’t worry… I still love you.”

Nightmare pushed himself up, staring deep into Dream’s eyes. It was Dream’s turn to fidget as he whispered, “I’m sorry.”

Nightmare smiled warmly. “I told you. I’m fine…” Nightmare paused as he turned away. “I liked it,” he muttered.

The other perked, not expecting that response, though he hesitated to make any further actions. He watched as Nightmare’s “eyebrows” furrowed. He seemed angry with himself. He shook. Dream felt Nightmare’s grip on his arms tighten.

Nightmare just bit his lip before speaking. “It just… felt so... wrong.” He dropped his head in guilt.

Something lit inside Dream. He smiled at the other, gingerly brushing his finger across the stains marking dry tears on Nightmare’s cheek. He cupped his other cheek, making Nightmare look at him. Dream shut his eyes as he brought their mouths together.

Nightmare felt a familiar warmth spread through his body as he kissed back. The kiss was gentle and loving. He couldn’t sense any ill intentions behind it. He felt Dream’s hand on the back of his head, forcing them closer.

Dream slipped a tongue into Nightmare’s mouth. Once he felt the other’s, he fondled it, pressing and pushing as both slipped by each other.

Dream smiled as Nightmare moaned quietly. He could feel his mind wandering off to the fantasies he previously had. He stealthily reached behind him into the cardboard box, pulling out a rope and straps.

Without missing a beat, Nightmare was pinned against the headboard, arms tied behind him and ankles fitted into straps, tied down onto the bed.

Dream ignored Nightmare’s protests of shrieking and shouting as he messed with the waistband on Nightmare’s pants. He crawled to Nightmare’s side, looking at his brooding and downcast expression, as he slipped his hand in.

Nightmare tensed as Dream’s fingers teasingly brushed against his member. He closed his eyes tightly as Dream rubbed his inner thighs and groped him. With Dream’s other hand, he teased the hard member through the fabric.

“D-Dream…”

Dream halted, looking to Nightmare. A pleading look crossed his face.

“Th-This isn’t right. W-w shouldn’t be d-doing this…”

Dreams looked wolfishly at Nightmare before casting his gaze back down. He started teasing again.

“W-Wait! Dream!”

Dream ignored Nightmare as he inserted a finger into his lone hole.

Nightmare jerked. “Dream, please! Stop!!”

Dream pulled in and out, adding another finger shortly after. Nightmare grit his teeth, biting back moans. All that was heard were his grunts and Dream fingering him.

Dream stole a glance at Nightmare, a sly smile making its way on his face. He inserted more fingers, brushing against the sensitive walls, determined to hear Nightmare’s cute sounds, but Nightmare was determined to keep them away.

Dream looked at Nightmare hard-on. Then, he curled his fingers.

“AAaaAahh~ No! Dream, stop this! Mmh~” Nightmare whimpered as Dream circled his prostate teasingly.

“Didn’t you like it, Nighty?” Dream mused as he slipped Nightmare’s shorts down, him shivering as the cold air hit his exposed bones.

“I-I did! I just…” Nightmare turned away, tears beginning to form.

“Just what?” Dream inquired, rubbing his thumb across Nightmare’s magic, teasing the head.

The other whimpered. “I like it… I just don’t want it.”

Dream hummed in response. “Are you sure? Because it seems like you need this.” He leaned down closer to Nightmare. “I love the way you act around me, brother~” Dream stroked the shaft painfully quick, causing the other to jolt. “You’re so obedient… I’m the only one who sees you like this… isn’t that great~?”

Nightmare bit his lip as Dream’s pace inside him and on his magic dick grew faster. He held back his moans as Dream’s seducing voice whispered to him.

“No one…” Dream paused. “Only me.”

Nightmare whined as a negative feeling emerged from the other. “D-Dream, are y-you j-je-jealous?”

Dream glanced at the other, Nightmare’s needy eyes nervously staring back at him.

“A little,” he murmured.

Nightmare glanced down, a prominent blush on his cheeks. “D-D-Dream…” he stammered, gaining the other’s attention. “P-please… k-keep go-going…”

A look of sympathy crossed Dream’s face as he removed his touch from Nightmare only to caressed his cheek once again. “Are you sure?”

“Did I fucking stutter?”

“Yes, actually. You did.”

“Stfu and go before I change my mind.”

Dream giggled. “Alright, Nightmare~” He slipped his hand back into the cardboard box of torture and used the other one to pleasure Nightmare’s member.

Dream pulled out three objects and pumped Nightmare’s dick faster. He arched his back and mewled quietly.

Dream went faster and faster and Nightmare felt himself coming closer. He curled over and moaned as he reached his peak, a white substance spurting on Dream’s hand.

Nightmare heaved, clearly exhausted. But Dream didn’t stop. He continued stroking the once again hard cock. Nightmare jerked back hard onto the pillow as the head was teased and rubbed. “D-Dream, n-no -ooOooh~ ! T-too much!” He moaned loudly as Dream pulled his sensitive mind closer to another orgasm.

Nightmare huffed and panted, crying in agony as Dream wrenched another orgasm out of him. But before he felt release, all movements stopped and a tight restriction hugged the base of his shaft.

Nightmare whimpered and sluggishly leaned forward to see a dark cock-ring squeezing tightly on his dick, preventing any kind of pleasure. He snapped back as he felt a vibration tickle his sensitive member. A little egg was stuck onto him, wires draped over his legs and connected to a remote.

He writhed as a cold, circular object nudged its way between his cheeks and stretched open his ass. Nightmare moaned gently as the plug settled inside him, his hole closing around the rim.

He lurched as it started to vibrate, a lengthy groan eliciting from him. He squirmed and moaned loudly as he was stimulated from both ends. “AaAaahHhH~!! Dream! HahH~ Hnngg-“

Dream smirked as he turned the vibrator up a few notches, amused as Nightmare drew out another wonderful moan. “Wow, brother. You’re so loud~” he teased, making his way into Nightmare’s view. “As much as I love hearing those sounds you make, I think we should shut you up for now~”

Dream rid himself of his shorts, revealing his own erection. Nightmare looked at Dream, eyes wide and lavender blush covering his cheeks. A smug grin made its way on Dream’s face. He stepped over Nightmare so his face was lined up with his faded, yellow dick.

“You know what to do, Nighty.”

Nightmare gulped, sweat rolling down his skull. He laughed nervously. “Hehe… I don’t think so…”

A hungry smile presented itself on Dream’s face. “I want you to suck it. No need to be embarrassed~ Just remember not to bite.”

Nightmare inhaled sharply before shakily parted his “lips.” Instead of doing his task, though, he winked and said, “I wouldn’t dream of doing that.”

Needless to say, Dream felt an angry emotion swarm inside him. He aggressively hooked his fingers in between Nightmare’s teeth, forcing them wide open.

He shoved his skull onto his cock. The warm tongue brushed against the base, resulting in a moan from Dream. He thrusted his hips, pushing the length into Nightmare’s mouth.

Nightmare choked as the dick prodded the back of his throat. He closed his sockets as he hesitantly wrapped his “lips” around the member. “Eyebrows” furrowed, he began to bob his head.

The purple tongue swirled and circled Dream, who had his hand clamped over his mouth to stifle his moans.

Nightmare opened a single eye to peak at Dream. Moans tore through the air, Dream’s tongue falling out of his wide open mouth. His hands rested on Nightmare’s skull, slightly nudging him closer.

“AaAhh~ Nightmare! So good~! Your mouth feels MmMMm~ so… goOod~! AAAaaHhhH!!”

Dream’s hands slid behind Nightmare. His eyes widened as he tried to pull back, tears stinging his eyes, but Dream gripped his skull and shoved his mouth onto his dick, deepthroating him.

Tears streamed down Nightmare’s cheeks as he choked on both the length and ropes of sweet cum flooding down his throat. Dream held him close, forcing him to swallow everything.

He finally pulled out, a milky liquid dribbling down Nightmare’s chin. Nightmare felt faint, eyes half lidded with tears still falling.

Dream’s thumb nudged the inside of Nightmare’s cheek, gently forcing his mouth open. He smiled ravishly at the other’s hazy expression. “Wow~... You took in a lot, didn’t you? Did that feel good~?”

Nightmare gulped before giving a tentative nod. Dream smiled, reaching over to a certain remote. He took Nightmare’s chin and forced him to make eye contact. Nightmare, still in his daze, failed to see Dream taking the remote.

His eyes bulged as he keened. Dream turned the little egg vibe to the highest setting, chucking as Nightmare moaned quietly. He pushed the vibe, applying extra pleasure to Nightmare’s dick. He grinned, satisfied as he drew out a louder moan.

Dream moves away from the other’s member, lower himself closer to the vibrations butt plug. He flicked the base, causing Nightmare to flinch. Amused, Dream flicked once again, a small yelp escaping the other’s mouth.

He gripped the base, and wriggled the object inside Nightmare. He moaned loudly as the cool pleasure brushed against and pressed into his prostate. He squirmed and his legs trembled, forcing himself back as the plug hovered near his prostate.

Nightmare whimpered as he felt his cock expand slightly, groaning painfully when the ring prevented and squeezed him from his release. Beads of sweat rolled down his face as he tried to push past the restraint, slumping dolefully when he failed.

Dream, who witnessed the action, smirked. “Do you need something, Nightmare? Hhmm~?”

Nightmare whined with a pleading expression, panting slightly. “P-pl-please! Let m-me cum!”

Dream seemed to ponder for a moment. “Hmmm… I dunno, brother. Should I?”

“Yes! YES! Please!! Dream, I can’t take it anymore!”

“Alright, Nighty~” Dream took the plug out of Nightmare and lined himself up with the hole. He paused when he heard a quiet giggle come from the other.

He looked up and Nightmare gravely. Nightmare giggled to himself, laughing as he noticed Dream’s worried expression.

“Hey, Dream… Don’t you think this is a little sansual?”

Dream stared blankly at the other, sighing and smiling at his silliness. “Of course.”

He suddenly shoved his whole length into Nightmare, cutting off the other’s giggling with a cry. Dream started moving quickly. Each roll of his hips are fast, pleasurable, and hard.

Nightmare moaned as Dream slammed into him, quickly stretching out his walls. There were cries of pain and pleasure sounding through the room with each thrust.

Dream groaned, “AaH~ Y-you’re so- mMmm~ w-warm… and t-t-tight!” He angles his hips in search for a sensitive bundle of nerves, smiling satisfiedly as he heard a loud moan from Nightmare.

“HHaaAAAh!! Dream~~! Please!!!!”

Dream leaned forward and began slamming into the prostate, Nightmare screaming loudly with each thrust. He cupped the other’s cheeks, caressing his smooth bones gently.

“You’re so beautiful~ Are you enjoying this?”

“Dream!! AAAaaahhHh~ More! More!! Dream, I need MORE! I need to cum!! PLEASE~!”

Dream chuckled softly as he stroked Nightmare’s trembling cock. He could feel his own member throbbing inside him. Kindly, he turned off the vibrator and took it off.

“Do you want this off, too?” Dream asked, motioning towards the cock ring.

Nightmare cried. “YES! Dream, please! Take it off!”

Dream chuckled darkly. “I don’t think so~ You’ll just have to bear with me.”

The other sobbed, frustrated as Dream started thrusting in harder. “Pl-please,” he cried, broken.

“Don’t worry. I’m already close, Nighty~”

“NnnG~” Nightmare bucked his hips in hopes of pleasure. “Please take it off…”

Dream reached down with shakey hands and wrapped his fingers around the shaft. He moved them up and down, receiving a frustrated groan as a result.

Dream groaned, himself. “Aaah~ Mare, I’m so close~ F-fuck.”

He tore the ring from its hold on Nightmare, eliciting a scream of pleasure.

“AAAaaAa! Dream~! Mmf-” Dream pulled them both into a kiss. Both moaned in pleasure, way too close to release.

Nightmare screamed as he finally came, hot liquid squirting out his dick And hope clenching tightly around Dream’s member.

Dream moaned loudly, feeling Nightmare’s tight walls squeeze him. He shoved in the whole length, spilling his seed inside and filling him up, ecto bulging slightly to accommodate the foreign magic.

Both of them panted loudly, Nightmare moaning quietly as he felt warmth fill him from the inside.

“Hah…. Dream……. I-”

“Shh… I love you.” Dream leaned down on Nightmare’s chest, nuzzling him gently. “And nothing will end that.”

“Dream… I lo- AAAhH!”

Dream quickly pulled out and shoved the already vibrating plug back into Nightmare, keeping all the fluids from escaping.

Dream quickly slipped some clothes on and bolted to the door.

“Wait! DREAM! GET BACK HERE, YOU ASSHOLE!!— aaAh~!”

Dream turned his head to watch Nightmare squirm. He was met with a flustered glare.

He just winked back. “I’ll be back later, brother~”

He closed the door, muffling any protests that came from his lover. 

**Notes for the Chapter:**

> To be continued...


End file.
